A Solution to the Strong CP Problem

G. Schierholz

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arXiv · hep-lat/9409019

A Solution to the Strong CP Problem

G. Schierholz

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Abstract

One may argue that QCD solves the strong CP problem by itself, without having to introduce new symmetries and particles. To test this idea, a lattice simulation is performed. The problem is investigated in the CP$^3$ model first. It is found that the model has a first order phase transition in $θ$ from a confining phase at small $θ$ to a deconfining phase at large $θ$, and that the critical value of $θ$ decreases towards zero as $β$ is taken to infinity. This suggests that $θ$ is tuned to zero in the continuum limit. Preliminary studies of the SU(2) Yang-Mills theory in four dimensions show a phase transition in $θ$ as well, so that it is quite likely that the strong CP problem in QCD is solved along the same line.

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G. Schierholz. 1994-09-26. A Solution to the Strong CP Problem. https://arxiv.org/abs/hep-lat/9409019

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